Make tests for access time less strict

- allows real fs tests to pass on file systems on XFS fs
- fixes #453

CHANGES.md

@@ -9,7 +9,8 @@ The release versions are PyPi releases.
     and `io.open`
 
 #### Fixes
-
+  * make tests for access time less strict to account for file systems that 
+    do not change it immediately ([#453](../../issues/453))
 
 ## [Version 3.5.2](https://pypi.python.org/pypi/pyfakefs/3.5.2)
 

pyfakefs/tests/fake_stat_time_test.py

@@ -284,7 +284,7 @@ def check_open_read_close_non_w_mode(self):
         self.assertEqual(read.st_ctime, closed.st_ctime)
 
         self.assertEqual(before.st_atime, opened.st_atime)
-        self.assertLessExceptWindows(opened.st_atime, read.st_atime)
+        self.assertLessEqual(opened.st_atime, read.st_atime)
         self.assertEqual(read.st_atime, closed.st_atime)
 
         self.assertEqual(before.st_mtime, opened.st_mtime)
@@ -301,7 +301,7 @@ def check_open_read_close_new_file(self):
         self.assertEqual(created.st_ctime, read.st_ctime)
         self.assertEqual(read.st_ctime, closed.st_ctime)
 
-        self.assertLessExceptWindows(created.st_atime, read.st_atime)
+        self.assertLessEqual(created.st_atime, read.st_atime)
         self.assertEqual(read.st_atime, closed.st_atime)
 
         self.assertEqual(created.st_mtime, read.st_mtime)
@@ -443,7 +443,7 @@ def test_open_read_close(self):
         self.assertEqual(read.st_ctime, closed.st_ctime)
 
         self.assertEqual(before.st_atime, opened.st_atime)
-        self.assertLessExceptWindows(opened.st_atime, read.st_atime)
+        self.assertLessEqual(opened.st_atime, read.st_atime)
         self.assertEqual(read.st_atime, closed.st_atime)
 
         self.assertLess(before.st_mtime, opened.st_mtime)
@@ -558,7 +558,7 @@ def test_open_read_flush_close(self):
         self.assertEqual(flushed.st_ctime, closed.st_ctime)
 
         self.assertEqual(before.st_atime, opened.st_atime)
-        self.assertLessExceptWindows(opened.st_atime, read.st_atime)
+        self.assertLessEqual(opened.st_atime, read.st_atime)
         self.assertEqual(read.st_atime, flushed.st_atime)
         self.assertEqual(flushed.st_atime, closed.st_atime)